API Rate Limit to 100 or Expect100Continue Question

I am looking for assistance for one of powershell command that is running in foreach loop – for @ 150 times.

Below command runs fine for 100 times and then start throwing error. it looks like it is client side-Powershell side error as our API vendor said, it is some sort of limit on powershell.

Command : Invoke-RestMethod -Uri https://SEPSERVER:8446/sepm/api/v1/computers?computerName=$SEPComputerMove -Headers $header -Method GET |select -Expandproperty numberOfElements -Debug


Invoke-RestMethod : The underlying connection was closed: An unexpected error occurred on a send.

  • CategoryInfo : InvalidOperation: (System.Net.HttpWebRequest:HttpWebRequest) [Invoke-RestMethod], WebException
  • FullyQualifiedErrorId : WebCmdletWebResponseException,Microsoft.PowerShell.Commands.InvokeRestMethodCommand

I have changed Expect100Continue to True. However it appears that, there is some other type of 100 limit based on user/rate limit per min? etc. Please advise us, If there


MaxIdleTime : 100000
UseNagleAlgorithm : True
ReceiveBufferSize : -1
Expect100Continue : True
IdleSince : 2/13/2020 3:35:26 PM
ProtocolVersion : 1.1
ConnectionName : https
ConnectionLimit : 10
CurrentConnections : 0
Certificate : System.Security.Cryptography.X509Certificates.X509Certificate
ClientCertificate :
SupportsPipelining : True


Hetal Soni

Seen this error when the session ends and you are still passing it in the header. How does the API handle sessions? Is there a correlation of time rather than the number of records?


Thank you very much for your response. You are right at the point. I have recreate script to break API call into batch of 90 and then add sleep for 90 seconds and then REAUTHNTICATE to API server and it seems to be working.

However i would like to know, is there anyway from Wireshark or some sort of debug to see if Powershell really sending expect100continue in the header? Does API server reject this request from client? Is expect 100contiue is enabled, does that means , power shell doesn’t have to reauthenticate to api server?

Thanks again for your support.

Hetal soni



Most api’s are rate limited. Try this.


Thanks for the response. really appericiated.

I have already raised value from 50 to 200 on SEP side, however as per SEP support, Powershell is restricting 100 API call, thus I have change Expect100Continue= True for Powershell-client side. However I am still seeing error @ 100 API call.

For Expect100Continue – Do SEP Server have to support this ? How do we verify that, Powershell ISE is sending Expect100Continue ? through wireshar? or enabling some sort of debug on powershell side?

All API’s do not work the same. They are going to have different rate limits, paging, record sizes, etc. that need to be taken into consideration. I’ve connected to hundreds of API’s and have never added a Expect100Continue in a header or anywhere else and collected a million records in single calls. There are common API vendors that software companies use, but the software company still needs to implement the features. It sounds like you are doing some kind of paging operation, how many records are you returning for each call? Is that adjustable? Explain the entire solution you are trying to engineer. There are X total records and your getting them at X records per call. The software vendor is going to be the best to assist you, they control the back-end and should have logging, but you can also tell them what you are doing and ask for guidance.